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dpb

valvejob wrote:
On Sat, 28 Jul 2007 08:30:05 -0500, wrote:

Because of our dry weather I noticed my electric fences were not
working very well. I soon discovered that I got shocks when I touched
the ground rod. I knew right away the ground was bad. I only had a 2
foot piece of galv. pipe. so I went to buy a real rod. The guy told
me I need three 8 foot rods spaced 10 ft. apart, and gave me a free
booklet put out by the Dare Company. Well, OK, they do say to use
three rods, but I think that's overkill. At the same time my 2 ft,
pipe was way under rated. So, I will put in a real 8 foot rod, but
only one. I'm sure that will help greatly.

However, here comes the question. They say to not place the fencer
ground rod closer than 40 feet to the house or barn ground rods. I
can not understand what the reasoning is for that? I also looked and
the rod I am replacing is 18 ft from the barn ground to the breaker
box. My other fencer (other barn) that rod is only about 11 feet away
and that one is set in a concrete slab so it would be very hard to
replace, however, it's only a foot from the water hydrant so that
seems ideal since the ground is always well soaked. In order to
change the one I am working on, I'd have to move the fencer to the
other end of the barn, which means changing the fence and adding an
outlet. Or, I'd have to run 20 ft of wire to the rod.

I dont understand why the closeness to the building (power) rod should
make any difference at all. Do you?

Thanks

Yes, I do. My fence charger generates 5,000 volts between the two
terminals and I assume yours is about the same.

If you have a poor ground and a shorted hot wire, then the ground
becomes -5,000 volts. If you tied that to your house ground then
your house ground would be at -5,000 volts.

It may never put the full charge on the house ground but in real life
it happens often enough to shock you and to kill small animals. Also
happens often enough that they put warnings about it on their
products.

There are lots of homes and farms that are floating many volts off the
ground or neutral line because of poor grounds due to poor soil.
Read recently where a dairy farmer had that problem with his 220 volt
neutral and his livestock were sensing it.

HV, low current and interrupters besides. You can grab a direct fence
charger and only get a good jolt...

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